ansitruecolortest

#!/usr/bin/env ruby
# print a 24x6 gradient behind "TRUE COLOR" and another behind "ANSI 256 COLOR"



def lerp888(x, y)
  black = [0,0,0]
  blue = [0,0,255]
  green = [0,255,0]
  cyan = [0,255,255]
end

# return the ANSI color for x, y on a 24x6 grid, numbered
# as follows:
#
#     x -->
#     012345678901234567890123
#     ------------------------
# y 0| 16  22  28  34  40  46
# | 1| 17  23  29  35  41  47
# v 2| 18  24  30  36  42  48
#   3| 19  25  31  37  43  49
#   4| 20  26  32  38  44  50
#   5| 21  27  33  39  45  51


def lerp256(x, y)
  # This is such a weird stupid lerp and I'm tired and I can't math.
  # It should be a lerp onto the 6x6 square and then stretched horizontally.
  # But I can do this awful thing in much less time...
  ray = [
    [16, 16, 16, 16, 22, 22, 22, 22, 28, 28, 28, 28, 34, 34, 34, 34, 40, 40, 40, 40, 46, 46, 46, 46],
    [17, 17, 17, 17, 23, 23, 23, 23, 29, 29, 29, 29, 35, 35, 35, 35, 41, 41, 41, 41, 47, 47, 47, 47],
    [18, 18, 18, 18, 24, 24, 24, 24, 30, 30, 30, 30, 36, 36, 36, 36, 42, 42, 42, 42, 48, 48, 48, 48],
    [19, 19, 19, 19, 25, 25, 25, 25, 31, 31, 31, 31, 37, 37, 37, 37, 43, 43, 43, 43, 49, 49, 49, 49],
    [20, 20, 20, 20, 26, 26, 26, 26, 32, 32, 32, 32, 38, 38, 38, 38, 44, 44, 44, 44, 50, 50, 50, 50],
    [21, 21, 21, 21, 27, 27, 27, 27, 33, 33, 33, 33, 39, 39, 39, 39, 45, 45, 45, 45, 51, 51, 51, 51],
  ]
  ray[y][x]
end
# ruby -e '"   TRUE COLOR   ".each_char.with_index { |c,i| print "\x1b[48;2;0;0;#{i*16+15}m#{c}"}; puts "\x1b[0m"'
# echo -e "\x1b[38;5;15;48;5;16m ANS\x1b[48;5;17mI 25\x1b[48;5;19m6 CO\x1b[48;5;21mLOR \x1b[0m"

puts "+------------------------+"
puts "|      8 BIT COLOR       |"
puts "+------------------------+"
[40,100].each do |offset|
  print "|"
  (0..7).each do |color|
    print "\x1b[#{color+offset}m   \x1b[0m"
  end
  puts "|"
end
puts "+------------------------+"


puts "+------------------------+"
puts "|     ANSI 256 COLOR     |"
puts "+------------------------+"
6.times do |y|
  print "|"
  24.times do |x|
    color = lerp256(x, y)
    #    char = " #{color} "[x%4]
    char = " "
    print "\x1b[48;5;#{color}m#{char}"
  end
  puts "\x1b[0m|"
end
puts "+------------------------+"

puts "+------------------------+"
puts "|    24-BIT TRUECOLOR    |"
puts "+------------------------+"
6.times do |y|
  blue = (255 * (y/6.0)).to_i
  print "|"
  24.times do |x|
    green = (255 * (x/24.0)).to_i
    char = " "
    print "\x1b[48;2;0;#{green};#{blue}m#{char}"
  end
  puts "\x1b[0m|"
end
puts "+------------------------+"

if ENV["TMUX"] && `tmux -V` < 'tmux 2.9'
  puts "\x1b[1mDO THESE COLORS LOOK BAD?\x1b[0m"
  puts "I see \x1b[31myou are running #{`tmux -V`.strip}\x1b[0m. Your truecolortest will probably look about like the 256-color test until you \x1b[32mupgrade to tmux 2.9\x1b[0m or so."
  puts "\x1b[1;31;107m   BEWARE THAT THIS MAY BREAK YOUR EXISTING TMUX CONFIG SO HOLD OFF UNTIL YOU'RE UP FOR AN OPS HASSLE    \x1b[0m"
end